Theodoee mueller



T. MUELLER. I Device for Making Bezels andBacks for Watch-Gases.

No. 226,870. Patented Apfil 27, I880.

WITNESSES ATTORNEY N. PETERS. PHOTO-UTHOGR WASHINGTON. Dv C.

' UNITED STATES PATENT Farce.

THEODORE MUELLER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THOMAS E. HAGSTOZ AND CHARLES N. THORPE, OF SAME PLACE.

DEVICE FOR MAKING BEZELS AND BACKS FOR WATCH-CASES.

SPECIFICATION formingpart of Letters Patent No. 226,870, dated April 27, 1880,

Application filed March 29, 1879 To all whom it may concern Be it known that 1, THEODORE MUELLER, of the city and county of Philadelphia, and State of Pennsylvania, have invented a new and useful lmprovementin the Manufacture of the Bezels and Backs of WatclrGases; and 1 -do hereby declare the following to be a sufficiently full, clear, and exact description thereof to enable others skilled in the art to make and use the said invention, reference being had to the accompanying drawings, which form a component part of this specification, and the letters of reference marked thereon.

The object of myinvention is to produce, with but a small amount of work, from a single piece of metal a bezel, back, or cap for a watch-case with such definite exactness of form and finish as to fit upon its appropriate rings on the watch-case center, and relates more particularly to the part known technically by watchcase makers as the snap. This has frequently been attempted to be made from a single piece of metal, but has never been accomplished with such desired certainty and 2 5 exactness as would compact the metal forming the snap-rim of the bezel, back, or cap to its best condition of hardness and stiffness, and of such precision of form as to require no part of the metal to be cut away on the exterior of the bezels,backs, or capsin finishing them to fit the centersa desideratum of first importance in the manufacture of watch-cases from plated metal.

The nature of my invention consists in the introduction of a peculiarly-formed rim or core, which can be introduced and withdrawn from the annular space inside of the bezels and watch backs and caps, so as to afford a firm support or counter-pressure during the finishing or concluding stamping or compressing operation, which determines the shape and size of the snap-rim.

My invention also relates to the construction of the dies whereby the watch-plate and the backs or caps are delivered from the dies.

Backs, caps, and bezels of watch-cases all have the snap necessary to fit them closely and firmly to the watch-center. The bezel is like a back or cap, except that it has an opening and a seat or bearing for retaining a glass or crys- 5o tal in position; but, so far as the snap is concerned, the process of manufacture is the same in all, and a description of one will apply equally to the others.

In the drawings, Figure 1 is a die and matrix 5 5 for forming backs, showing the first step in the operation. A thin plate of metal, of which the back is to be formed, is placed under the die, which is then brought down on the matrix. The inner edge of the die, acting upon the outer 6o edge of the matrix, cuts from the plate a circular disk of the metal of the exact size required for the back. Further movement of the die presses the disk into the saucer-depression of the matrix and produces the form shown at H-the result of the first stage of the process. The ring encircling the matrix'is supported by the pins D D. These pins and the central pillar, E, are all connected with the plate F, supported by the springs G G. As the die comes down the ring and the pillar yield, and as the die is withdrawn they are lifted by-the springs to their normal position and the waste metal is delivered by the ring 0, and the cap or back by the pillar E, so that no time is lost or delay occasioned by either of these pieces sticking, as is often the case in the old forms.

The second stage in the process takes the back H and, by the action of a die having its inner face conical, brings it into the shape shown at I, Fig. 3, ready for the finishing-die. (Shown in section in Fig.2.) This dieis formed of the case K, having in it the movable center L, around the stem of which a spiral spring is coiled, pressing it out. A collapsible ring of .85 steel, M, fits loosely within the case and is confined therein by screws, permitting lateral movement. The lower outer edge of this steel ring is of the exact form required of the inner edge of the back, cap, or bezel, and when 001- lapsed as the (lie stands normally this ring passes through the reversed edge (as shown at I, Fig. 3) of the back; but when pressure is applied to it and the center strikes the backin the matrix the conical form of the movable cen- 5 ter'L spreads the collapsible ring within thereversed edge of the back, and, while pressing it against the matrix and into the required shape,

h'olds it up firmly and prevents its collapsing, and the resulting product is a back fitting perfectly and accurately upon the watch-center, and not needing turning out by hand to adapt it to its place.

An incidental advantage of the use of this die is that the great pressure to which the metal is subjected in forcing it into the groove of the collapsible ring to form the snap as thus described condenses the metal to a degree of hardness which conduces greatly to its durability and Wearing qualities.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a die and matrix for forming watch backs and caps, the combination of the matrix TH. MUELLER.

Witnesses:

HENRY PHAFANT, Jr., B. H. LoWRY. 

